Kev is quite right about it being a day-lily (Hemerocallis), rather than a lily (Lilium). I was going to post a similar comment. I will add, though, it's still a member of the lily family. (Along with genera like Smilacina, Maianthemum, Alllium, Tofieldia, Clintonia, Smilax, Uvularia, Zigadenus, Polygonatum, Streptopus and even Asparagus. Probably others I've overlooked, too.) I'm not sure what point I was trying to make with this post, other than common names can be confusing.

Cheers,

Rob